Random generator exercise

[ncouch]

I am in a bit of a quandry trying to tweak this script.  It's main function
is to generate a random sequence of from 1-9 alpha and numerical characters.
The main problem I am having is updating the global value of x after each
run of the repeat loop.

As it stands right now it keeps resetting the value back to "1" after each
loop.  I understand why it does this, but don't understand why I can't reset
the value after each run.  Anyone have any ideas on how I might do this.

Here is the script so far:

=================================================

on MouseUp
  -- setting things up
  put empty into field "random"
  put empty into field "rn"
  put empty into field "valx"
  ask "How many characters do you want? (# between 1 and 9)"
  put it into field "valrn"
  put it into valrn
  put 1 into x

  -- generating the random sequence
  repeat until x=(valrn+1)
    put random(2) into rc
    put rc into line x of field "rn"

    if rc=1 then
      ralpha -- an alpha character
    else rnum -- a number

    add 1 to x
  end repeat
end MouseUp

on ralpha
  global x
  put random(26) into rn
  get char rn of field "alpha"
  put it into char x of field "random"
end ralpha

on rnum
  global x
  put random(9) into rn
  put rn into char x of field "random"
end rnum

=================================================

Cheers,

Nate